Sánchez was confirmed as an Arsenal player after travelling to London to undertake a medical and sign a four-year contract worth around £130,000 a week.

The deal makes forward Sánchez the second most expensive player in Arsenal’s history behind Mesut Özil, who joined for £42.5 million last year. His signing should be quickly followed by the confirmation of right-back Mathieu Debuchy’s £11 million move to the Emirates from Newcastle United.

As revealed by Telegraph Sport on June 24, manager Wenger made his first move for Sánchez while away in Brazil at the World Cup where the forward starred for Chile, scoring two goals in four appearances.

“As many people have seen during the World Cup this summer, Alexis is a fantastic footballer and we are delighted that he is joining us at Arsenal,” said Wenger.

“Alexis will add power, creativity and much quality to our squad and we are all looking forward to him joining up with us in a few weeks. He has consistently produced top-quality performances at the highest level for a number of seasons now and we are all excited to see him integrate into the Arsenal squad. I’m sure all Arsenal supporters will join me in welcoming Alexis to our club.”

Sánchez made a total of 88 appearances for Barca, scoring 39 goals during three seasons in Spain.

Liverpool wanted to take the 25-year-old as part of Barca’s deal to sign Luis Suarez and Juventus were also keen on Sánchez.

But the lure of London and playing for Wenger swayed Sánchez towards the Emirates and he will meet up with his new Arsenal team-mates at the end of this month, having made it to the last 16 of the World Cup with Chile.

Sánchez is expected to make his first Arsenal appearance in the Emirates Cup, which takes place on August 2 and August 3.

“I’m so happy to be joining Arsenal, a club which has a great manager, a fantastic squad of players, huge support around the world and a great stadium in London,” said Sánchez.

“I’m looking forward to meeting my new team-mates and to be playing for Arsenal in the Premier League and Champions League. I will give my best to Arsenal and want to make all the supporters happy.” Sánchez can play anywhere across the front three and will add goals and pace to Wenger’s squad.

He has made 71 appearances for Chile, scoring 24 goals, and started his club career with Cobreloa, based in Calama in north Chile, where he spent a season before moving to Santiago-based Colo-Colo, where he won the Chilean Primera Division in 2007.

After impressive performances in Chile between 2005 and 2007, Sánchez went on loan to Argentine side River Plate, where he added the Argentinian Primera Division to his honours.

Following his success in South America, Sánchez made a permanent move to Serie A side Udinese in 2008, where he spent three seasons, scoring 20 goals from 95 appearances.

His displays in Italy prompted Manchester City to launch a huge bid to try to sign Sánchez in 2011, but Barcelona made a rival offer and the player decided to move to the Nou Camp.

Having confirmed the signing of Sánchez and agreed a deal with Debuchy, Wenger will concentrate on trying to sign a new midfielder, a central defender, a back-up goalkeeper and another striker.